A.增大了流動(dòng)截面; B.減小了阻力系數(shù); C.增加了當(dāng)量長(zhǎng)度; D.增加了當(dāng)量直徑
A.位能 B.動(dòng)能 C.靜壓能 D.熱能
A.α=2 B.α=3 C.α=0.4 D.α=0.25